Portable telephones such as cellular telephones are in common use. A hand-held cellular telephone enjoys the convenience of portability. A car mounted cellular phone is also known.
A car-mounted cellular phone has certain advantages. For example, since the car-mounted phone uses an external antenna, it may get better cellular reception. An external antenna may also enable the car kit to transmit with higher power than is allowable with a hand held phone.
A xe2x80x9ccar kitxe2x80x9d is often an interface between the automobile and the telephone. The car kit can act as a part of the hand-held cellular phone. The hand-held phone plugs into the car kit, and uses the structure of the car kit for transmission and reception, e.g., to an external antenna. The car kit can also have a hands-free kit that allows the user to talk on the telephone without using their hands. Some jurisdictions, in fact, require a user""s hands to be free while driving.
Automobile-mounted communication devices can be installed into automobiles for various purposes. For example, the Telematics (TM) and Mayday (TM) systems install a transceiver into the vehicle. These systems can be used for signaling law enforcement authorities when the automobile is stolen or carjacked. These systems include radios therein.
Car kits can often only be used with the cellular phone itself being present. If the user forgets to bring their phone into the car, then the car kit becomes useless.
An automobile mounted cellular phone can be used without a hand-held cellular phone being present. However, this requires that the automobile mounted cellular phone have a separate telephone number from the handheld cellular phone, and also requires that the user pay two monthly service fees.
The present application defines a new telephone interface device adapted to be mounted in a vehicle. The device can interface with a portable telephone, and take on the character of the portable telephone (from claims here).
According to a particularly preferred embodiment, the system uses a low power consumption, wireless protocol, which includes automated service discovery, spread spectrum operation, clock synchronization, defines unique identities, and allows multiple access via time slot system. According to a particularly preferred embodiment, this protocol can be the so-called Bluetooth protocol.